Television and like apparatus



Aug. 2, 1932. J. L. BAIRD TELEVISIQN AND LIKE APPARATUS Filed Oct. 7, 1929 V duction of stored Patented Aug. 2, 1932 PATENT OFFICE.

JOHN LOGIE BAIRD, or LoNnoN,

LONDON, ENGLAND, A

ENGLAND, ASSIGNOR 'r'o TELEVISION LIMITED, 01

BRITISH COMPANY TELEVISION AND LIKE APPARATUS Application filed October 7, 1929, Serial No. 397,983, and in Great Britain October 10, 1928.

This invention is for improvements in or relating to television and like apparatus, and has for its object to provide improved apparatus for use in connection with the reproor recorded images.

In a television system of the type in which signals are obtained in the receiving station and are used to modulate a source of light by a varying electric current. In addition to, or instead of using this varying electric current, to modulate the source of light, it may be used to make a permanent record on a gramophone disc. Thus a permanent image-record may be made of the transmitted signals and a visible image may subsequently be reproduced by using the record in a gramophone having an electrical pick-up, the current from which modulates a suitable source of light, in a televison receiver.

Hitherto the exploring means of the receiver has been separate from the gramophone mechanism and has had to be synchronized with it.

According to this invention there is provided in apparatus of-the type described for reconstituting a visible image from a recor thereof, stored or recorded on a gramophone like disc, a disc having a plurality of spirally arranged sets of holes formed in its marginal portion, each set of said holes efiecting one complete traversal of the reconstituted image. Thus the holes may be formed in the marginal portion of the turntable of a gramophone, or they may be formed in the marginal portion of the disc bearing the image record to be reproduced.

Instead of holes in the disc, lenses, prisms, mirrors or the like may be used.

The figure of the drawing shows a convenient form of apparatus according to the present invention which will now be described by way of example.

A disc bearing the image-record to be reproduced is rotated by the turntable 2 of an apparatus resembling an ordinary gramohone. The disc is of less diameterthan the turntable, and thus a marginal ring of the turntable is exposed. A series of spirals of holes 3 is arranged round this marginal portion and constitutes the exploring device.

7 any gearing The relative disposition of the holes corresponds to that of the holes in the exploring device which has been used for I'GCOIdlIlQOI transmitting the image, and is such that when the record is once correctly set to give a clear image the setting remains correct to the end of the record.

The track of the record disc 1 is engaged by the needle of an electrical pick-u 7 the current from which may be ampli ed and used to modulate the intensity of illumination of a suitable source of light 4. As the turntable rotates, the light from the source & passes ture 6 to the eye of an observer (not shown). The reconstituted image may be viewed di rectly, or through a lens. Y

fThis invention obviates the necessity for other than that already contained in an ordinary gramophone which is thus readily adaptable for the reproduction of images of moving scenes or objects re-' corded on a gramophone-like record I claimr 1. In apparatus of the class described, the combination'with arotatable element having a record thereon. representing variations in light intensity derived by scanning an image, of means for .reproducingthe variations in light intensity from the record thereof, and scanning means associated with said first named means for deflecting light beams from the latter across a field of vision, said scanning means being carried by said element.

2. In apparatus oi the class described, the combination with a rotatable element having a record thereon representing variations in light intensity 'lerived by scanning an image,

of means for reproduclng the variations in light intensity from the record thereof, and

througheach of the holes 3 in succession, and is reflected by the viewing aper-i scanning means associated with said first named means for defiecting'light beams from the latter across a field of vision,said scan ning means beingcarried by saidelement and comprising aime'mber having a plurality of series of spirally arranged apertures therein, whereby the image may be reconstructed a plurality of times for each rotation of said scanning element and scanning means.

3. In apparatus of the class described, the combination with a rotatable disc of the gramophone type having variations in light intensity mechanically recorded thereon, of means for producing currentpulsations corresponding to said variations from the mechanical record, a scanning means rotating with said disc, and a source of light activated by said current pulsations and associated with said scanning means, said scanning means comprising a turntable for supporting said disc and provided with a plurality of series of spirally arranged apertures, whereby the image may be reconstructed a plurality of times for each rotation of said scanning element and scanning means.

4. In apparatus of the class described, the combination with a rotatable disc of the gramophone type having variations in light intensity mechanically recorded thereon, of means for producing current pulsations corresponding to said variations from the mechanical record, a scanning means rotating with said disc, and asource-of light activated by said current pulsations and associated with said scanning means, said scanning means comprising an integral .portion of said disc provided with a plurality of series of spirally arranged apertures, whereby the image may be reconstructed a plurality of times for each rotation of said scanning element and scanning means.

5. Television apparatus of the kind de scribed comprising a gramophone-like turntable provided integrally with a plurality of series of light transmitting devices, each series being adapted to scan the complete field of vision, a disc of the gramopho-ne type adapted to be supported on said turntable, said disc having variations in light intensity mechanically recorded thereon, means for translating mechanical vibrations derived from the disc record into electrical impulses and means for translating said electrical impulses into variations of light intensity, said two means being adapted to cooperate with the said series of light transmitting devices to produce an image whereof the variations of light intensity constitute a graphical representation, the image being reconstituted a plurality of times for each rotation of the turntable.

6. A rotatable gramophone-like turntable of diameter greater than that of an image record disc carried thereon and provided in its marginal portion with a plurality of series of light transmitting devices, each series be ing adapted to completely reconstitute the image whereof said disc contains a record.

7. In apparatus of the class described, the combination with a rotatable disc of the gramophone type having variations in light intensity mechanically recorded thereon, of means for producing current pulsations cor 

